Method for producing milk protein fibres

ABSTRACT

The disclosure relates to milk protein micro and super-micro fibres (MPM) and polymer nano fibres (MPN) produced according to a spinning method, in which at least one protein, which is obtained from milk and which can be thermally plasticized, is plasticized using a plasticizing agent, such as for example, water or glycerol at temperatures between room temperature and 140° C. by means of mechanical stress in a spinning system and is spun using a spinneret to obtain the MPN- and MPM fibres.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/EP2012/072422, filed on Nov. 12, 2012, and published in German as WO2013/068596 A1 on May 16, 2013. This application claims the benefit andpriority of German Application No. 10 2011 118 432.9, filed on Nov. 12,2011. The entire disclosures of the above applications are incorporatedherein by reference.

BACKGROUND

This section provides background information related to the presentdisclosure which is not necessarily prior art.

TECHNICAL FIELD

Methods for producing polymer nano fibers (MPN fibers) are described inliterature and known to the man skilled in the art. Within the scope ofthe present application, this fiber group also comprises milk proteinmicro and supermicro fibers (MPM fibers).

DISCUSSION

Electrospinning processes for producing protein fibers are for exampledescribed in the patents EP 09156540.8 and EP 08162122.9. Centrifugespinning processes which are suitable for producing nano fibers are forexample disclosed in EP 624 665 A, EP 0813622 and EP 1 088 918 A. Inthese centrifuge spinning processes, the polymer containing solution ordispersion is brought into a rotating container and discharged from thecontainer in form of fibers by means of centrifugal forces.

The German Patent 09170024.5 (BASF) describes a method for producingcoated protein fibers by means of a centrifuge spinning technology,wherein it is essential with respect to the invention that the fibersare contacted with a 2-cyanoacrylate acid ester during or after theirproduction. These esters are inviscid or intentionally thickened estersof the cyanoacrylic acid which are placed on the market as monomers in1K form and are converted into the real adhesive polymer in the jointgap by a polymerization reaction. From U.S. Pat. No. 3,215,725 (1) andDE-A 41 22 475, 2-cyanoacrylate acid esters of monovalent and bivalentalcohols are known as light protection agents for synthetic materialsand varnishes. These compounds however have the technical disadvantageof a relatively high volatility. Since they are only partiallycompatible with many organic materials, in particular polyolefines, theytend to migrate, over all when they are stored in warm condition, and toshow exudation effects which are related thereto. 2-cyanoacrylate acidesters polymerize spontaneously to polycyanoacrylate under the effect ofair humidity. They are thus used as reactive adhesives (superadhesives). Even if the patent application 95938395.1/0790980 (BASF)describes new 2-cyanoacrylate acid esters which shall avoid the presentproblems, and cyanoacrylic acid is known as wound closure,cyanoacrylates which can furthermore be mixed with epoxy resin,acrylates etc. are considered to be harmful to health due to the risk ofquick hardening.

This can be especially a problem for medical applications, where thenano fibers shall enable the penetration of the skin and the receptionof drugs, because then toxicologic substances are received by the skin.For improving the water and humidity resistance of polymer or proteinfibers or fiber surface structures produced from these ones, diversemeasures have been described in literature.

Herein it is a possible method to influence the properties of thepolymers by cross linking reactions.

In spite of these known methods it has not been possible so far to givepolymer fiber materials made of renewable raw materials (over allprotein based) a required water and humidity resistance, which is acondition for textile fibers, without addition of acrylates and fossilraw materials. The use of acrylates and fossil raw materials should be,if possible, largely avoided for reasons of health.

Additionally, the described methods are not economic and cannot be usedindustrially. If plasticizing operations are described, they are relatedto long swelling times before the polymer is brought onto thecorresponding spinning facility. This leads to uneconomic workingoperations.

SUMMARY

It is an object of the invention to eliminate the above mentioneddisadvantages and to give polymer fiber materials, preferably made ofrenewable raw materials (over all protein based), a required water orhumidity resistance, preferably without addition of acrylates and fossilraw materials.

Herein, the invention shall in particular reduce the processing time andthe use of chemicals and preferably, and to the greatest possibleextend, produce the MPN and MPM fibers from renewable and biodegradableraw materials. Simultaneously, the water and energy consumption shall bedecreased and the productivity be increased.

The aim is achieved by a method according to the teachings of thepresent disclosure.

The present invention aims at MPN and MPM fibers which are produced by acontinuous or discontinuous process from a composition which comprisesdestrcutured milk proteins, biodegradable thermoplastic polymers andsoftening agents.

Herein, at least one protein obtained from milk or a protein producedfrom bacteria is plasticized, optionally together with a plasticizer, attemperatures comprised between room temperature and 140° C. undermechanical stress.

The invention is based upon the knowledge that the milk proteins and inparticular casein and the derivates thereof can be plasticized and inthis manner be polymerized. It is preferably provided that theplasticizing takes place at temperatures of preferably up to 140° C.

For achieving an even more gentle treatment, the protein is intenselymixed or kneaded with a plasticizer and simultaneously subjected tomechanical stress. Herein, the temperature which is required for theplasticizing is considerably reduced by means of the plasticizer.

The milk protein is preferably casein or lactalbumin or soy protein.

The protein obtained from milk can be produced in situ by precipitationfrom milk. According to a first procedure, the milk in form of a mixturewith lab, other suitable enzymes or acid can be immediately introducedinto the process as flocculated mixture or the pressed-off flocculatedprotein can be used in humid form. According to another optionalprocedure, a previously separately obtained, if necessary prepared, pureor mixed protein, i.e. a protein fraction from milk, can be used, forexample in the form of a dried powder.

The protein fraction can also be produced by ultrafiltration or by usingcell cultures. Furthermore, the milk proteins can be modified in otherprocess steps for example by additional salts such as sodium andpotassium, such that a casein is produced.

The milk protein used according to the invention can be mixed with otherproteins in a proportion of preferably up to 70% by mass with respect tothe milk protein. For this, other albumins, such as ovalbumin andvegetable proteins, in particular lupine protein, soy protein or wheatproteins, in particular gluten can be used.

The mixture of solvent and protein is heated up, usually under pressureconditions and shear, in order to accelerate the cross linking process.Chemical and enzymatic agents can also be used, in order todestructurize and to cross link, to oxidize and to derivatize, toetherify, to saponify and to esterify the milk proteins. Usually, themilk proteins are destructurized by dissolving them in water. The milkproteins are completely destructurized, if there are no clots whichinfluence the fiber spinning process.

In the present invention, a plasticizer can be used in order todestructurize the milk proteins and to enable the milk proteins to flow,i.e. to produce thermoplastic milk proteins. The same plasticizer orother plasticizers can be used in order to increase the meltingprocessability, or two separate plasticizers can be used. Theplasticizers can also improve the flexibility of the final products,wherein it is assumed that this is due to the reduction of the glasstransition temperature of the composition caused by the plasticizer. Theplasticizers are essentially compatible with the polymer constituents ofthe present invention, such that the plasticizers can effectively modifythe properties of the composition. As it is used here, the expression“essentially compatible” means that if the plasticizer is heated up to ahigher temperature than the softening and/or melting temperature of thecomposition, the plasticizer will be able to form an essentiallyhomogenous mixture with milk proteins.

The plasticizer is preferably water which is used in a proportioncomprised between 20 and 80% with regard to the weight of the protein,preferably in a proportion comprised between approximately 40 and 50% bymass of the protein content.

Instead of water or mixed with this one, other plasticizers, inparticular alcohols, poly alcohols, carbohydrates in aqueous solutionand in particular aqueous polysaccharide solutions can be used.

In detail, the following plasticizers and associated proportions arepreferred:—hydrogen bridges forming organic compounds without hydroxylgroup, for example urea—and derivates,—animal proteins, e.g.gelatin,—vegetable proteins such as for example cotton,—soy beams,—andsunflower proteins,—esters of producing acids which are biodegradable,e.g. citric acid, adipic acid, stearic acid, oleicacid,—hydrocarbon-based acids, e.g. ethylene acrylic acid, ethylenemaleic acid, butadiene acrylic acid, butadiene maleic acid, propyleneacrylic acid, propylene maleic acid,—sugars, for example maltose,lactose, sucrose, fructose, maltodextrose, glycerin, pentaerythrit andsugar alcohols, e.g. malitol, mannitol, sorbitol, xylitol,—polyols, e.g.hexanetriol, glycols and the like, also mixtures and polymers,—sugarhydrides, e.g. sorbitan,—esters, such as for example glycerin acetate,(mono, -di, -triacetate) dimethyl and diethylsuccinate and relatedesters, glycerin propionates, (mono, -di, -tripropionate) butanoates,stereates, phthalate esters. These are non limiting examples of hydroxylsoftening agents. Important influencing factors are the affinity to theproteins, the quantity of proteins and the molecular weight. Glycerinand sugar alcohols belong to the most important softening agents. Thepercentages of the softening agents are for example comprised between 5%and 55%, but they can also be comprised between 2% and 75%. Any desiredalcohols, polyols, esters and polyesters can be preferably used in apercentage of up to 30% by weight in the polymer mixture.

The rheological features are of a particular importance for the polymermixture, in order to achieve a good processing. The solidification understretch flow is required for forming a stable polymer structure. Themelting temperature is mostly in a temperature range comprised between30° C. and 190° C. Temperatures above these values should be reduced bymeans of diluents and softening agents.

The biodegradability of the polymers, i.e. their decomposition by livingcreatures and their enzymes is an important feature of the polymeric MPNand MPM fibers.

Among the biodegradable thermoplastic polymers which are for examplesuitable for being used in the present invention, are lactic acidpolymers, lactide polymers, glycolide polymers, including their homo-and co-polymers and mixtures thereof; aliphatic polyesters of dibasicdioles/acids; aliphatic polyesteramides, aromatic polyesters, also ofmodified polyethylene terephthalates and polybutylene terephthalates;polycaprolactones; aliphatic/aromatic copolyesters;poly(3-hydroxyalkanoates), including their copolymers and/or other-valerates, -hexanoates and -alkanoates, polyesters and dialkanoylpolymers, polyamides and copolymers of polyethylene/vinyl alcohol.

These compounds are for example and preferably suitable as biodegradablethermoplastic polymer of this invention: polyvinyl alcohol and polyvinylcopolymers, aliphatic amide and ester copolymers which are formed bymonomers such as for example dialcohols (1,4-butandiol, 1,3-propandiol,1,6-hexandiol etc.) or ethylene glycol and diethylene glycol, aliphaticpolyesteramides, (aliphatic esters are formed with aliphatic amides) orby means of other reactions , such as for example lactic acid withdiamines and dicarbonic acid dichlorides, dioles with carbonic acids,caprolacton and caprolactam, or ester prepolymers with diisocyanates,dicarbonic acids, especially succinic acid, oxalic acid and adipic acidand the esters thereof, hydroxycarbonic acids, lactones, amino alcohols(for example ethanolamine, propanolamine), cyclic lactams, aminocarbonicacids (e.g. aminocaproic acid), dicarbonic acids and diamines (e.g. saltmixtures of dicarbonic acids) and mixtures thereof. Polyesters such asfor example oligoesters can also be used.

Polybutylene succinate/adipate copolymer; polyalkylene succinates;polypentamethyl succinates; polyhexamethyl succinates; polyheptamethylsuccinates; polyoctamethyl succinates; polyalkylene oxalates, such aspolyethylene oxalate and polybutylene oxalate, polyalkylene succinatecopolymers, such as polyethylene succinate/adiapte copolymer andpolyalkylene oxalate copolymers, such as polybutylene oxalate/succinatecopolymer and polybutylene oxalate/adipate copolymer; polybutyleneoxalate/succinate/adipate terpolymers; and mixtures thereof are nonlimiting examples of aliphatic polyesters of dibasic acids/dioles whichare for example produced by polymerization of acids and alcohols orring-opening reactions and are suitable for producing a polymer.

In the production of biodegradable polymers, aliphatic/aromaticcopolyesters can also be used. These copolyesters are formed in acondensation reaction from dicarbonic acids (and derivates) such asmalonic, succinic, glutaric, adipic, pimelic, azelaic, sebacic, fumaric,2,2-dimethyl glutaric, suberic, 1,3-cyclopentane dicarbonic,1,4-cyclohexane dicarbonic, 1,3 cyclohexane dicarbonic, diglycolic,itaconic, maleic, 2,5-norbomandicarbonic, 1,4-terephtalic,1,3-terephtalic, 2,6-naphtoeic , 1,5 naphtoeic acid, esters formingderivates and mixtures thereof and dioles, for example ethylene glycol,diethylene glycol, triethylene glycol, tetraethylene glycol, propyleneglycol, 1,3-propane diole, 2,2 dimethyl-1,3-propane diole, 1,3-butanediole, 1,4-butane diole, 1,5-pentane diole, 1,6-hexane diole,2,2,4-trimethyl-1,6-hexane diole, thiodiethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexane dimethanol,2,2,4,4-tetramethyl-1,3-cyclobutane diole and combinations thereof.Examples of such aliphatic/aromatic copolyesters include mixtures ofpoly(tetramethylene glutarate-co-terephthalate), poly(tetramethyleneglutarate-co-terephthalate), poly(tetramethyleneglutarate-co-terephthalate), poly(tetramethyleneglutarate-co-terephthalate), poly(tetramethyleneglutarate-co-terephthalate-co-diglycolate),poly(ethyleneglutarate-co-terephthalate),poly(tetramethyleneadipate-co-terephthalate), a mixture having a ratioof 85/15 of poly(tetramethylenesuccinate-co-terephthalate),poly(tetramethylene-co-ethylene-glutarate-co-terephthalate),poly(tetramethylene-co-ethyleneglutarate-co terephthalate).

The processability of the protein mass can be modified by othermaterials, in order to influence the physical and mechanical propertiesof the protein mass, but also those of the final product. Non limitingexamples include thermoplastic polymers, crystallization accelerators orinhibitors, odor masking agents, cross linking agents, emulsifiers,salts, lubricants, surfactants, cyclodextrines, greasing agents, otheroptical brighteners, antioxidants, processing agents, flame retardants,dye stuffs, pigments, filler materials, proteins and their alkali salts,waxes, adhesive resins, extenders and mixtures thereof. These auxiliaryagents are bound to the protein matrix and influence the properties ofthis one.

Salts can be added to the molten mass. Non limiting examples of saltsinclude sodium chloride, potassium chloride, sodium sulfate, ammoniumsulfate and mixtures thereof. Salts can influence the solubility of theprotein in water, but also the mechanical properties. Salts can serve asbinding agents between the protein molecules.

Lubricants can, on the other hand, influence the stability of thepolymer. They can reduce the stickiness of the polymer and decrease thefriction coefficient. Polyethylene is a non limiting example.

The physical properties of the polymer mass can be influenced by otherproteins; these ones include, without limitation, for example vegetableproteins such as sunflower protein or animal proteins such as gelatine.Water soluble polysaccharides and water soluble synthetic polymers suchas polyacrylic acids can also influence the mechanical properties.

Monoglycerides and diglycerides and phosphatides as well as other animaland vegetable fats can influence and favour the flow characteristics ofthe biopolymer.

Inorganic filler materials also belong to the optional additives and canbe used as processing agents. Possible examples, which do not limit theuse, are oxides, silicates, carbonates, lime, clay, limestone andkieselguhr and inorganic salts. Stearate based salts and colophony canbe used for modifying the protein mixture.

Amino acids which are constituents of the proteins and peptides can beadded to the polymer mass in order to enhance special pleated sheetstructures or mechanical properties. Without limitation, glutamic acid,histidine, trytophane etc. are mentioned as examples.

Enzymes, surfactants, acids, serpines as well as phenolic plantmolecules are other additives which can contribute as cross linkingagents to improve the mechanical properties and the resistance in waterand the protease resistance.

Other additives can be desirable in dependence on the respective finaluse of the intended product. Wet strength is for example a requiredproperty of most of the products. Therefore, it is required to addresins comprising a wet-strength as cross linking agents.

Other natural polymers can also be added as additives. Possible examplesof natural polymers are, without limiting the selection, albumins, soyprotein, zein protein, chitosan and cellulose, “polylactide” and “PLA”,which can be used in a percentage comprised between 0.1% and 80%.

Apart from natural polymers, other synthetic polymers such as inter aliapolyvinyl alcohol as well as polyester or ethers such as polyethyleneglycol, aldehydes such as glutaraldehyde and acrylic acids can be used.

These ones also include non-degradable polymers which are used independence on the final use of the MPN and MPM fibers. Thermoplasticsynthetic materials which can be used for copolymerization are included,such as—without having a limiting effect—for example polypropylene,polyethylene, polyamide, polyester and copolymers thereof. Other highmolecular polymers are also possible.

Carbohydrates and polysaccharides as well as amyloses, oligosaccharidesand chenodesoxicholic acids can be used as other auxiliary agents andadditives.

Salts, carbonic acids, dicarbonic acids and carbonates as well as theiranhydrides, salts and esters can also be used as additional crosslinking agents. Hydroxides, butylesters as well as aliphatichydrocarbons present other possibilities to cross link the molecules toeach other and to form macromolecules.

The addition of other agents is not excluded. Additives and auxiliaryagents, such as lipophile, hydrophobic, hydrophile, hydroscopicadditions, glossing agents and cross linking agents can be especiallyprovided. The additives and auxiliary agents shall altogether not exceeda proportion of preferably maximum about 30% by mass with regard to theprotein. Vegetable oils, alcohols, fats can be chosen as lipophileadditions which slightly hydrophobize the fiber already during theplasticizing operation. Furthermore, waxes and fats can be used whichadditionally give the fiber stability. Preferred waxes are carnauba wax,beeswax, candelilla wax and other naturally obtained waxes.

After the MPN and MPM fiber has been formed, the fiber can be furtherprocessed or the bound substance can be treated. A hydrophile orhydrophobic surface treatment can be added, in order to adjust thesurface energy and the chemical condition of the substance. HydrophobicMPN and MPM fibers can be for example treated with wetting agents, inorder to facilitate the absorption of aqueous liquids. A bound substancecan also be treated with a topic solution which contains surfactants,pigments, lubricants, salt, enzymes or other materials, in order tofurther adjust the surface properties of the MPN and MPM fiber.

For achieving that the MPM and MPN fiber or the surface structuresthereof meet the stricter requirements by means of improved propertiesfor a certain purpose, they are preferably produced, apart from thehitherto known and described production methods, by means of a nanocentrifuge spinning unit in order to increase the productivity. For thisthe spinning mass, which is also called spinning solution or spinnablesolution, is produced with the viscosity required for the nanocentrifuge spinning process. The spinning mass is produced by thecontinuous or discontinuous method which is known to the man skilled inthe art and from literature, preferably by mixing or extruding apre-mixture while adding additives or by preparing the spinning solutionby dosing in the basic materials and additives during the mixing orextruding.

The production of the MPN fibers can be realized according to knownmethods, for example by means of an electro-spinning or a centrifugespinning method, force spinning, melt-blow-spinning or a nano centrifugespinning process.

The method in which water is used as solvent and plasticizer preventsany difficulties with respect to labour law, toxicology and productapproval.

Thanks to the plasticizing operation, the spinning mass corresponds to apolymer in which the materials are transferred into a plastic state byheating them up and are deformed in this manner. Herein, the temperatureexceeds the glass transition temperature of the protein such that thisone is converted from the amorphous state into the rubber-like plasticstate.

After the MPN and MPM fiber has left for example the spinning jet, thisfiber can be immediately processed further, preferably for forming afiber surface structure.

Immediately after the formed MPN and MPM fiber has left the jet or in atleast one subsequent processing step, the fiber can alternatively befurther processed to a plied yarn, can be in particular twisted, beloosely coiled up to a cotton wool or be further processed to a fleece.

In order to improve the properties of the described fibers,bio-components can be used before and after the spinning mass gets outof the jet.

As a further development of the invention, the MPN and MPM fiber canalso pass through a bath for a further treatment, wherein this processis not especially preferred and usually not required. Alternatively, thefiber can be subjected to a spraying treatment after having left thejet. Herein, for example smoothing agents, waxes, lipophiles or crosslinking agents can be applied to the surface of the fiber. In the caseof cross linking agents, the above mentioned ones are preferred:generally different salt solutions, preferably a calcium chloridesolution, a dialdehyde starch solution or an aqueous lactic acid.Alternatively, the fiber can be subjected to a gas treatment or an icetreatment or a drying and blowing treatment or a ionic treatment or a UVtreatment or an enzymatic treatment as well as to a renaturation bymeans of salts or esterification, etherification, saponification oranother cross linking process as well as to a needling and hydroentangling process and to calendaring etc.

The obtained MPN and MPM fibers and the products which are made of theseones can be used for all imaginable purposes. Thus, they can beprocessed to form all types of textile fabrics, woven fabrics, knittedfabrics, crocheted textile fabrics, yarns, ropes, fleeces, felts etc.and also be processed further accordingly, e.g. be coated. The MPN andMPM fibers and fiber surface structures according to the invention canbe used ijn numerous fields of application and be completely orpartially composed of the fiber surface structures, for example ascoating and/or constituent. They can be used as non-woven fabrics orfleeces, in particular in the field of cosmetics, textiles, medicalproducts, hygienic and cleaning products, cell culture and catalystcarriers as well as bubbles, filter and membrane parts, coalescers etc.Furthermore, cotton wools, wound dressings, implants, loose fiberinsulating materials, light-weight building materials and sclera-likefiber surface structures can be made of the MPN and MPM fibers accordingto the invention.

The fibers of the present invention which are composed of severalconstituents can be present in many different configurations.Constituent, such as used here, means, according to definition, thechemical substance or the material. Fibers can comprise mono componentor multiple component configurations. Component, such as used here, isdefined as a separate part of the fiber which is in a spatialrelationship with another part of the fiber.

The advantages obtained by the invention are inter alia that, in theproduction of MPN and MPM fibers according to the invention, it becomespossible to reduce the substances which present a health risk and areenvironmentally harmful during the process and in the fiber itself.Besides, the fiber is biodegradable.

Furthermore, considerable resources of energy, water, time and manpowercan be saved, which enhances the environmental protection and improvesthe economic efficiency. The particularly advantageous properties of theMPN and MPM fibers are attributed to solidifying structural changes(tertiary structure) during the plasticizing operation.

The MPN fibers in the nano range, preferably comprising a diameter of80-500 nanometers, including filaments, fiber surface structures orbio-components, are preferably produced by means of a nano centrifugespinning unit in order to enable a highest possible productivity. Allproduction methods of the described nano fibers and micro fibers, inparticular the MPM fibers which are finer than 1 dtex and microsuperfibers which are finer than 0.3 dtex, which production methods areknown to the man skilled in the art and from literature, can be usedwithout any exception. It is essential with respect to the inventionthat a homogenously plasticized polymer, preferably a biogen biopolymer,can be produced that is biodegradable. Unfortunately, it has not beenpossible so far to develop fibers on this base which are water resistantand sufficiently resistant to proteases, acids and alkalis. Preferably,the use of petroleum-based raw materials and/or organic solvents, inparticular for fibers having skin contact or which are even used aswound dressing, as hygiene or childcare articles, just to mention a fewexamples, shall be reduced or even excluded.

For MPN and MPM fibers which are preferably produced from renewable rawmaterials with a proportion of milk proteins and are characterized byfeatures such as water resistance, high protease resistance, sufficientmechanical properties such as tensile strength and tear resistance, andare elastic, antiallergic, antibacterial and biodegradable, it isfurthermore possible to influence the properties of the protein fiberaccording to the requirements of the intended purpose by changing theadditions of raw materials.

EXAMPLES

In the following, the invention will be described in detail by means ofan exemplary embodiment. The exemplary embodiment only serves toillustrating purposes and shall not limit the invention. On the base ofthis exemplary embodiment and his know-how, the man skilled in the artcan find other possible embodiments by varying the parameters.

Example 1: Production of a milk protein spinning mass. The extrusion isrealized by a twin-screw extruder type 30 E of the company Dr. Collinhaving a diameter of 30 mm. The MPN fiber is produced by means of nanocentrifuge spinning technology of the equipment engineering Fa. Dienes.

The heating is realized by four cylinder heating zones with thefollowing temperature development: 65° C., 74° C., 75° C., 60° C.:

temperature 65 74 74 74 75 60 function material water plasticizingoutlet zone head jet supply supply zone heating I II II II III IV zone

The casein powder is supplied via a vibrating conveyor. Water is addedby means of a peristaltic pump. The additives are added by means ofother dosing devices. The fiber thickness is defined by the jetstrength. The fiber can for example have a thickness of 80 nm.

BRIEF DESCRIPTION OF THE DRAWING

The drawing described herein is for illustrative purposes only ofselected embodiments and not all possible implementations, and is notintended to limit the scope of the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Example embodiments will now be described more fully with reference tothe accompanying drawing.

The course of the extrusion process and the development of the MPM andMPN centrifuge spinning become additionally apparent in FIG. 1. The rawmaterials are dosed into the extruder via a dosing device 1 and thepolymer mass is mixed.

Afterwards, the extruded material is supplied to a spinning pump 3 andto a nano spinning centrifuge 4, wherein it passes afterwards throughthe post-treatment.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. Individual elements or featuresof a particular embodiment are generally not limited to that particularembodiment, but, where applicable, are interchangeable and can be usedin a selected embodiment, even if not specifically shown or described.The same may also be varied in many ways. Such variations are not to beregarded as a departure from the disclosure, and all such modificationsare intended to be included within the scope of the disclosure.

1. A method for the production of milk protein nano fibers and/or mesofibers (MPN fibers), preferably comprising a diameter comprised between80 nm and 500 nm, characterized in that said fibers are produced from ahomogenous polymer on the base of proteins obtained from milk byaddition of heat and a plasticizer and by using an electro-spinning,centrifuge spinning, force spinning, melt-blown-spinning or a nanocentrifuge spinning method.
 2. A method according to claim 1,characterized in that the MPN fibers are produced from a homogenouspolymer, preferably a bio-polymer of renewable raw materials, or arecoated with this one.
 3. A method for the production of milk proteinmicro fibers and milk protein micro-super fibers (MPM fibers),preferably comprising a diameter of less than 1 dtex, characterized inthat the MPM fibers are produced from a homogenous polymer, preferably abio-polymer of renewable raw materials, or are coated with this one. 4.A method according to one of the preceding claims, characterized in thatthe production of the MPN and MPM fibers is a continuous or adiscontinuous process.
 5. A method according to one of the precedingclaims, characterized in that the homogenous polymer that is composed ofmacromolecules is produced before the real spinning process of the MPNand MPM fibers by means of a continuous or discontinuous process undermechanical stress.
 6. A method according to one of the preceding claims,characterized in that the plasticizer is a constituent of themacromolecules.
 7. A method according to one of the preceding claims,characterized in that the plasticizing operation is carried out in amixer, a kneading device, an extruder or an injection moulding machine.8. A method according to one of the preceding claims, characterized inthat other additives and auxiliary agents are added to the base materialto be plasticized, optionally by admixing before or during theplasticizing operation.
 9. A method according to one of the precedingclaims, characterized in that at least one protein obtained from milk isplasticized together with a plasticizer under mechanical stress and ispreferably spun to fibers through a jet.
 10. A method according to oneof the preceding claims, characterized in that the plasticizing takesplace at temperatures of up to 140° C.
 11. A method according to one ofthe preceding claims, characterized in that the protein obtained frommilk is either produced in situ by precipitation from milk or is used inform of a protein that has been separately obtained before and, ifrequired, been prepared or is used in form of a protein fraction.
 12. Amethod according to one of the preceding claims, characterized in thatthe proteins obtained from milk are obtained from bacteria.
 13. A methodaccording to one of the preceding claims, characterized in that theproteins obtained from milk are obtained by gas treatment or filtration.14. A method according to one of the preceding claims, characterized inthat the proteins obtained from milk, in particular casein, lactalbuminor soy protein are obtained from goat's milk, sheep's milk, cow's milkor soy milk.
 15. A method according to one of the preceding claims,characterized in that the plasticizer is selected from the group: water,aqueous carbohydrate solution and in particular aqueous polysaccharides,oligosaccharides, proteins, alcohol, polyacohol, fats, acids, aminoacid, peptides, salts, cations, enzymes or mixtures thereof as well astheir oxidation.
 16. A method according to one of the preceding claims,characterized in that the MPN and MPM fibers are dried and post-treated,in that they pass through a bath and are subjected to a sprayingtreatment, a gas treatment, an ice treatment, a drying and blowingtreatment, a ionic treatment, a UV treatment, an infrared treatment, anenzymatic treatment, a needling and hydro entangling process, as well asto a renaturation by means of salts or alcohols, esters and ethers,esterification, etherification or saponification or another crosslinking or coating process or calendering process.
 17. A methodaccording to one of the preceding claims, characterized in that thepolymer mass or the MPM or MPN fibers are destructured, oxidized,derivatized, etherified, esterified or saponified during or after theprocess by means of chemical or enzymatic substances.
 18. A methodaccording to one of the preceding claims, characterized in that aminoacids are added to the polymer mass.
 19. A method according to one ofthe preceding claims, characterized in that the polymer mass is mixedwith or post-treated by protease inhibitors, preferably enzymes,surfactants, acids, serpines, phenolic molecules of plants and/orpolysaccharides.
 20. A method according to one of the preceding claims,characterized in that the MPN and MPM fibers are produced bycopolymerization of mixtures of two or more different monomers and/orproduction of bi-component or multi-component fibers.
 21. A milk proteinfiber product which contains MPN and MPM fibers which contain athermally mechanically plasticized milk protein, in particular producedby a method according to one of the claims 1 through
 20. 22. A use ofmilk protein fiber products according to claim 21 as coating and/orconstituent of non woven fabrics or fleeces, loose cotton wools or pliedyarns, in particular in the field of cosmetics, textiles, medicalproducts, hygiene and cleaning products, cell culture and catalystcarriers as well as filter and membrane parts.